Bicycle frame



FIG. 1 is a rear and right side perspective view of a bicycle frame showing our new design;

FIG. 2 is a rear elevation view thereof;

FIG. 3 is a front elevation view thereof;

FIG. 4 is a left side elevation view thereof;

FIG. 5 is a right side elevation view thereof;

FIG. 6 is a top plan view thereof; and,

FIG. 7 is a bottom plan view thereof.

The broken lines in the drawings illustrate portions of the bicycle frame that form no part of the claimed design. 

CLAIM We claim the ornamental design for a bicycle frame, as shown and described. 